Blast-furnace operation



Dec. 10, 1929. w. A. HAVEN 1,738,577

BLAST FURNACE OPERATION,

Filed April 9, 1927 2 Sheets-Sheet 1 I N VEN TOR.

A TTORNEY$ Dec. 10, 1929. w. A. HAVEN 1,738,577

BLAST FURNACE OPERATION Filed April 9. 192'! Sheets- Sheet 2 INVENTOR. 6/77/7672? /7 Ha we M 73mg."

A TTORNEYS Patented Dec. 10, 1929 UNETED STATES WILLIAM A. HAVEN, OF YOUNGSTOWN, OHIO BLAST-FURNACE ornnarron Application filed April 9.

In blast furance operation, the materials supplied at the top progressively work down as space is gained below, chiefly by the combustion of the coke. In some instances operation may become irregular, and the column of material sticks and hangs, and difficulties are encountered which may produce serious danger, even including explosion and destruction of the furnace. Furnace operation such m as to avoid tendencies to such irregularities is accordingly highly desirable.

To the accomplishment of the foregoing and related ends, the invention, then, consists of the features hereinafter fully described [.5 and particularly pointed out in the claims, the annexed drawing and the following description setting forth in detail but one of the various ways in which the principle of the invention may be applied.

In said annexed drawing Fig. 1 is a side elevation, part in section, showing an embodiment of my invention; Fig. 2 is a sectional detail on enlarged scale; Fig. 3 is a section taken on a plane indicated by the line III-III, Fig. 2; and Figs. 4, 5 and 6 show various modified arrangements.

I have found that the processes going on in the active zone of a furnace in blast may be largely influenced by the character of the air as current, and improved operation may be had where instead of a smoothly supplied current of air, the air stream is fluctuated in rather abrupt vibrations. Just why this should be so is not at present clear, whether by reason of an improved cleaning of the surfaces of the coke from ash films, or from improved elimination of occluded gases on the glowing coke, or from vibration assisting mechanically or chemically. I accordingly content myself to here with statement of the fact without commitment as to any theory.

In accordance with my invention, I employ the tuyere T and stove system arranged as customary, and for the blast a source of air supply, and the air is caused to fluctuate or vibrate, preferably with rather sharp or abrupt vibrations. An'advantageous arrangement may comprise a turbo type blower 3- drivcn at high speed by a suitable driving en gine or motor, this producing the air blast 1927. Serial m 182312.

most eficiently from the standpoint of engineering operation, and interposed in the connection between the furnace Fis a pulsator or fluctuator 5 asit may be termed. This may vary somewhat in its detail, involvingessentially a means for causing afluctuation or pulsation of the blast in waves. An advantageous construction comprises a rotor cage 6 mounted in a suitable casing 7 and having a drive shaft 6 operatedby a motor or the like. The casing 7 hasoppositejports 9 connecting in the line, and the rotor cage 6 also has opposite ports 10, such that as the shaft 6 and the cage 6 are rotated, the ports 10 will intermittently come in line with the ports 8 of the casing and at such instants allow of free flow of the air stream. At the other portions of the rotation cycle, however, the walls 11 having fenestrations 12 pass across the ports 8 of the casing and impart a fluctuation or vibration to the air flow.

In operating in accordance with my im: provement, the furnace being charged as usual, the blast is supplied from the blower source 3, and is brought into fluctuation or vibration by the pulsator or fluctuator, and is supplied into the reaction zone of the furnace. Operation proceeds, it is found, with marked smoothness and regularity.

lVhileusually it is preferable to locate the fiuctuator between the air source and the stove, as indicated in Fig. 4-, in some cases it may be located between the stove and the furnace, as in Fig. 1. In some cases also I contemplate placing itin the downcomer l7 beyond the furnace, as in Fig. 6. The advantages of the invention are generally realized in greatest degree, however, with fluctuations applied from the feed side and, for example, witha vibration rate of about 7 5 vibrations per minute. In Fig. 5 is shown a reciprocatory fluctuator on the pipe a which is receiving the air supply from a suitable compressor of any preferred type, not shown, the fluctuator having a cylinder 14 in communication with the pipe, and the plunger 13 being driven by a engine 15 having a valve gear 16.

Other modes of applying the principle of y the invention may be employed, change being made as regards the details disclosed, prolcc vided the steps or means stated in any of the following claims, or the equivalent of such, be employed. 7

I therefore particularly point out and dis- 5 tinctly claim as my invention 1. The combination of a blast furnace, a tuyere, an air compressor for supplying an air blast. and means controllable to cause the 1 blast to fluctuate regularly with a force insuf- 10 ficient to bodily displace the fuel bed.

2. The combination of a blast furnace, a' tuyere, a rotary air compressor in-communication therewith, and an independently controllable rotary fluctuator interposed between 15 the compressor and the tuyere to produce a blast fluctuating regularly with a force insufficient to-bodily displacethe fuel bed.

3'. In blast furnace apparatus, the combination of an air compressor, a tuyere for en- 29 try,- of air to the furnace, anda fluctuator betweenthe pump-and tuyere, said fiuctuator including a casing, a rotary cylindrical cage thereinhaving spaced ports'for passage ofthe air, and'means for rotatingsaidcage.

' :5 Signed by me, this'7th day of April, 1927.

WILLIAM A. HAVEN. 

